Researchers analyze the mechanics of dolphin sex

CT scans allow scientists to measure the dynamics of penetration and identify important contact points between male and female genitalia.

A CT scan shows how the elaborate genitalia of male and female bottlenose dolphins fits together. Photo by Dara Orbach, Dalhousie University

April 24 (UPI) -- Researchers have devised a unique set of scientific strategies for analyzing the sexual mechanics of marine mammals.

Most recently, scientists used the method to better understand how the oddly shaped genitalia of male and female dolphins fit together.

"While it may seem intuitive that the penis fits well into the vagina during copulation, the biomechanics and details of the anatomical fit can be quite complex and have seldom been explored," Dara Orbach, a postdoctoral fellow at Dalhousie University and research associate at Mount Holyoke College, said in a news release. "Whales, dolphins and porpoises have unusual vaginal folds, spirals and recesses that the penis and sperm must navigate through to successfully fertilize the egg."

The new research method begins with a male dolphin, porpoise or seal specimen that has died from natural causes. Orbach and her colleagues developed a way to inflate a specimen's penis to full erection. Researchers can then use the penis to simulate sex with vaginal tissue samples.

CT scans allow scientists to measure the dynamics of penetration and identify important contact points between male and female genitalia.

Researchers say a map of a marine mammal's "anatomical landmarks" -- important points of sexual contact -- can help conservationists properly stimulate genitalia during artificial insemination.

As part of their latest research efforts, scientists molded silicone models of dolphin vaginas to better understand how the sexual anatomy of male and female dolphins coevolved.